from manim import *

class CustomCurve(VMobject):
    def __init__(self, **kwargs):
        super().__init__(**kwargs)
        # 定义自定义曲线的控制点
        points = [
            [33, 10, 0],
            [34,-1,0],
            [43,-2,0]
        ]
        self.set_points_smoothly(points)
class math3(MovingCameraScene):
    def construct(self):
        self.camera.background_color = BLACK  # 设置背景颜色
        self.camera.frame_width = 100  # 设置边框宽度
        self.camera.frame_height = 60  # 设置边框高度
        self.camera.pixel_height = 1080  # 设置像素高度
        self.camera.pixel_width = 1920  # 设置像素宽度
        self.camera.center = ORIGIN  # 设置中心点位置
        self.camera.scale_factor = 1.0  # 设置缩放因子
        #设置横线
        for i in range(6*2+1):       
            dot1=Dot([-50,5*(i-6),0]).set_opacity(0.5)
            dot2=Dot([50,5*(i-6),0]).set_opacity(0.5)
            if i==6:
                line1=Line(dot1,dot2).set_color(WHITE).set_opacity(0.5)
                
            else:
                line1=Line(dot1,dot2).set_color(WHITE).set_opacity(0.5)
               
            self.add(dot1,dot2,line1)
        #设置竖线
        for i in range(10*2+1):        
            dot3=Dot([(i-10)*5,-30,0]).set_opacity(0.5)
            dot4=Dot([(i-10)*5,30,0]).set_opacity(0.5)
            if i==10:
                line2=Line(dot3,dot4).set_color(WHITE).set_opacity(0.5)
                
            else:
                line2=Line(dot3,dot4).set_color(WHITE).set_opacity(0.5)
            self.add(dot3,dot4,line2)
        #设置三个点
        dot1 = Dot(radius=1, color=RED)  
        dot1.move_to([-47.5,27.5,0]) 
        dot2 = Dot(radius=1, color=YELLOW)  
        dot2.move_to([-42.5,27.5,0])  
        dot3 = Dot(radius=1, color=GREEN)  
        dot3.move_to([-37.5,27.5,0])
         #镜头跟进效果 
        self.camera.frame.save_state()
         
        #镜头拉回
          #分析文本
        #text100=MarkupText("<b><i>分析/解：</i></b>",color=PINK).scale(5.0).move_to([-38,12.5,0])
        self.play(FadeIn(dot1),run_time=0.1)
        self.play(FadeIn(dot2),run_time=0.1)
        self.play(FadeIn(dot3),run_time=0.1)

        text = Tex(
                    r"\text{非P积分}",color=YELLOW
                   ,tex_template=TexTemplateLibrary.ctex).scale(5.0).move_to([-25,0,0])
        self.play(Write(text))
        arrow = Arrow(start=[-18,2,0],end=[-5,10,0],color=RED
                       , stroke_width=20, tip_length=1)

        self.play(GrowArrow(arrow))
        text1 = Tex(
                    r"\text{转化}",color=GREEN
                   ,tex_template=TexTemplateLibrary.ctex).scale(5.0).move_to([-17,7,0])
        
        text2 = Tex(
                    r"\text{P积分}",color=YELLOW
                   ,tex_template=TexTemplateLibrary.ctex).scale(5.0).move_to([0,10,0])
        self.play(Write(text2),Write(text1))

        arrow1 = Arrow(start=[5,10,0],end=[18,2,0],color=RED
                       , stroke_width=20, tip_length=1)

        self.play(GrowArrow(arrow1))

        text3 = Tex(
                    r"\text{看趋势}",color=GREEN
                   ,tex_template=TexTemplateLibrary.ctex).scale(5.0).move_to([17,7,0])
        self.play(Write(text3))
        arrow2 = Arrow(start=[-18,0,0],end=[18,0,0],color=RED
                       , stroke_width=20, tip_length=1)
        

         # 创建坐标系
        axes = Axes(
            x_range=[-3, 10, 3],  # 设置 x 轴范围，从 -π 到 π，步长为 π
            y_range=[-3, 10, 3],  # 设置 y 轴范围，从 -1.5 到 1.5，步长为 0.5
            axis_config={"color": WHITE, "stroke_width": 30},  # 设置坐标轴的颜色和线宽
            x_length=20,  # 控制 x 轴长度
            y_length=20,  # 控制 y 轴长度
        )
        axes.move_to([35, 0, 0])  # 移动坐标系的位置

        # 绘制 1/x 函数图像
        # 分为两部分以避开 x=0
        #graph_left = axes.plot(lambda x: 5/x, color=BLUE, stroke_width=30, x_range=[-5, -0.1])
        #graph_right = axes.plot(lambda x: 5/x, color=PURE_RED, stroke_width=30, x_range=[0.1, 10])
        
       

        title = Tex(
                    r"$\dfrac{1}{x}$",color=GREEN
                   ,tex_template=TexTemplateLibrary.ctex).scale(5.0).move_to([35,14,0])

       


        #self.play(Create(arrow10),Create(text15))
        # 将所有元素添加到场景中
        #self.play(Create(axes), Create(labels), Create(graph2))
         # 显示图像
        curve = CustomCurve(color=PURE_RED, stroke_width=20)
        
        self.play(Create(axes))
        self.play( Write(title), Create(curve))






        text6 = Tex(
                    r"\text{极限等价}",color=BLUE
                   ,tex_template=TexTemplateLibrary.ctex).scale(5.0).move_to([-20,15,0])
        self.play(Write(text6))

        self.play(GrowArrow(arrow2))
        text4 = Tex(
                    r"\text{看趋势}",color=GREEN
                   ,tex_template=TexTemplateLibrary.ctex).scale(5.0).move_to([0,3,0])
        text5 = Tex(
                    r"\text{含指,对函数}",color=GREEN
                   ,tex_template=TexTemplateLibrary.ctex).scale(5.0).move_to([0,-3,0])
        self.play(Write(text4),Write(text5))
        self.wait()